Drive mechanism engaging means

ABSTRACT

A drive mechanism engaging means is disclosed which may be used for a garage door operator to engage and disengage a chain as an example of a flexible drive member which is driven from a motor and speed-reducing drive train. The engaging means selectively engages and disengages a drive carriage from the chain so that in the event of electrical power failure, for example, the load carriage may be disengaged from the chain so that the garage door, which is fixed to the load carriage, may be manually operated to open and close the door. The engaging means may be actuated by a handle to be moved against a yieldable spring to stress the spring and thus release the load carriage from connection with the chain. The foregoing abstract is merely a resume of one general application, is not a complete discussion of all principles of operation or applications, and is not to be construed as a limitation on the scope of the claimed subject matter.

United States Patent [72] Inventor Alvin J. Carli I Sebring, Ohio [21]Appl. No. 886,984 [22] Filed Dec. 22, 1969 [45] Patented Dec. 28, 1971[73] Assignee The Alliance Manufacturing Company, Inc.

[54] DRIVE MECHANISM ENGAGING MEANS 13 Claims, 4 Drawing Figs.

[52] U.S.Cl 74/8921, 49/139 [51] Int. Cl Fl6h 27/02 [50] Field ofSearch74/8921, 25; 114/179, 180, 181, 182;49/139, 199; 160/193 [56] ReferencesCited UNlTED STATES PATENTS 2,861,800 11/1958 McKee et al 74/89213,051,014 8/1962 Houk 49/139 3,066,729 12/1962 Gessell 49/139 3,264,7853/1966 Miller 49/139 FOREIGN PATENTS 74,244 11/1948 Norway 114/17912/1921 Great Britain 5/1930 France ABSTRACT: A drive mechanism engagingmeans is disclosed which may be used for a garage door operator toengage and disengage a chain as an example of a flexible drive memberwhich is driven from a motor and speed-reducing drive train. Theengaging means selectively engages and disengages a drive carriage fromthe chain so that in the event of electrical power failure, for example,the load carriage may be disengaged from the chain so that the garagedoor, which is fixed to the load carriage, may be manually operated toopen and close the door. The engaging means may be actuated by a handleto be moved against a yieldable spring to stress the spring and thusrelease the load carriage from connection with the chain. The foregoingabstract is merely a resume of one general application, is not acomplete discussion of all principles of operation or applications, andis not to be construed as a limitation on the scope of the claimedsubject matter.

PATENTEU [151281971 SHEET 1 OF 2 Fig. 2

INVENTOR. ALv/N J. CAQL/ PATENTEDDEBZBISTI SHEET 2 OF 2 3,830,094

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ATTOENE Y5 DRIVE MECHANISM ENGAGING MEANS BACKGROUND OF THE INVENTION Indrive mechanisms for loads such as garage door operators, many differentforms have been devised in the prior art to connect the door operatordrive mechanism to the garage door to be moved. Such garage dooroperator is a great convenience but on rare occasions in event ofelectrical power failure the motor will not open the door, of course,and thus some means must be provided to disengage the door operator fromthe door so that the door may be manually operated. In many sectionalgarage doors of the overhead acting type which slide upwardly on a trackto a position adjacent the ceiling of the garage, the garage dooroperator has some drive train which moves longitudinally along thegarage ceiling, thus moving a load carriage longitudinally along thispath. The drive train includes a door arm usually of an L-shapepivotally connected to the load carriage and also pivotally connected tothe top section of the sectional garage door. This same construction isalso used with slab or one-piece garage doors which are pivoted to swingupwardly adjacent the garage ceiling when in an open position. The priorart has known many different forms of disengagement means whichdisengaged the door arm pivotal connection and the load carriage whichis reciprocally moved longitudinally along the garage ceiling. Thispermitted the L-shape door arm to hang downwardly when disconnected fromthe load carriage, and thus the garage door could manually be opened andclosed. However, this has the very great disadvantage that the door armwhich is an L-shape and might be about 2 feet long and of heavy ironconstruction, was left pivotally attached to the upper end of the garagedoor. Thus when the garage door was manually moved upwardly to an openposition, if the person doing this was not careful, the garage door armcould swing free and puncture a hole in the top of an automobile or inthe rear window or windshield of the automobile parked in the garage.Still worse it could act as a lethal weapon hitting someone in the headand could cause severe damage. This was all the more dangerous becausegenerally the garage door manufacturer did not put any printed warningson the garage door operator about such dangerous operation and becausethis electrical power failure only rarely occurred, the person doing thegarage door opening would forget from one time to the next that this wassuch a potential hazard.

In other prior art devices the means to disconnect the garage door fromthe door operator was very unhandy or very awkward or very difficult toaccomplish, usually provided as a sort of an afterthought and in manycases merely consisted of taking out one of the pivot pins somewhere inthe drive train.

SUMMARY OF THE INVENTION The invention may be incorporated in a drivemechanism for a load comprising, in combination, a frame, a motor onsaid frame, a speed-reducing drive train on said frame and having aninput from said motor, a rotatable output on said drive train, arotatable idler on said frame, a flexible drive member encircling saidrotatable output and idler, a load carriage, means for longitudinallyguiding movements of said carriage generally parallel to a portion ofsaid flexible drive member, means for attaching said load carriage to aload to be moved, and engaging means selectively engaging anddisengaging said load carriage and said flexible drive member.

An object of the invention is to provide a selectable engaging anddisengaging means for a drive mechanism such as for a Another object ofthe invention is to provide a lock bar which may selectively be movedbetween engaged and disengaged positions relative to a drive chain.

Another object of the invention is to provide a lock bar which isyieldably urged toward engagement with a chain and which may belongitudinally moved and rotated so that a latch will latch this lockbar in a disengaged condition relative to the chain.

Another object of the invention is to provide a garage door operatorwith an endless chain wherein a load carriage connected to the garagedoor is selectively engageable directly with one run of this chain.

Other objects and a fuller understanding of the invention may be had byreferring to the following description and claims, taken in conjunctionwith the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side view of the completedrive mechanism embodying the invention;

FIG. 2 is an enlarged side view of the engaging means of the invention;

FIG. 3 is a sectional view on line 3-3 of FIG. 2; and

FIG. 4 is an end view of the engaging means of FIG. 2.

DESCRIPTION OF THE PREFERRED EMBODIMENT FIG. I of the drawing shows thecomplete drive mechanism 11 to reversibly move a load 12 shown as asectional overhead garage door. This door may be a one-piece ortwo-piece door which is pivoted to move to an open position adjacent thegarage ceiling or as shown it may be a sectional door rolling upwardlywith rollers in a track 13. The drive mechanism 11 includes a frame 15on which a motor 16 and a speed-reducing drive train 17 is located. Theframe 15 is adapted to be fastened in any suitable manner to the ceiling18 of the garage. A frame extension 19 extends from the frame 15 and isfastened to the header 20 of the garage. This frame extension 19 maytake the form of a T-shaped bar for stiffness and strength and has anupright stem 21 and a T-shaped flange 22, as shown in FIG. 4.

The drive train 17 has an output or drive sprocket 24 and an idlersprocket or idler roller 25 is provided near the header end of the frameextension 19. A roller chain 26 is a flexible drive member and in thispreferred embodiment is an endless chain which is trained around thedrive sprocket 24 and the idler roller 25. As such this chain 26 hasfirst and second runs 27 and 28 on opposite sides of the stem 21 of theframe extension 19. A load carriage 30 is guided for longitudinalsliding movements on the frame extension 19. An L-shaped door arm 31 hasa pivot connection at 32 to the load carriage 30 and a pivot connection33 to the top of the door 12. Engaging means 35 is provided toselectively engage and disengage the load carriage 30 and the flexibledrive member or chain 26.

The FIGS. 2, 3 and 4 show in greater detail the construction andoperation of the engaging means 35. The load carriage 30 is made of somematerial which will readily slide longitudinally on the frame extension19. For strength and economy this frame extension 19 may be an ordinarycold-rolled steel T-bar. The load carriage 30 is made of some materialwhich will readily slide longitudinally on the frame extension 19. Theload carriage 30 may be fabricated from sheet metal or may be a die-castmetal or a molded plastic material. This load carriage 30 has a base 36plus two flanges 37 and 38 which partially wrap around the flanged head22 of the frame extension 19 and thus establish the longitudinallyguided movement of this load carriage 30. A fork 40 is fixedly attachedto the bottom of the base 36 and the upper end of the door arm 31 slidesbetween this fork and is pivoted thereto by the pivot connection 32 sothat as the load carriage 30 reciprocates, this pulls open or pushesclosed the door 12. First second and third vertically spaced horizontalflanges 41, 42 and 43 are fixed on the load carriage 30. Verticallyaligned apertures 44, 45 and 46 are disposed in the flanges 41, 42 and43, respectively. A longitudinally slidable and rotatable lock bar 48 isdisposed for movement in the apertures 44, 45 and 46. A handle 49 isprovided at the lower end of the lock bar 48. A cross pin 50 is disposedin a aperture in the lock bar 48 and this cross pin 50 is disposed belowthe second flange 42. A compression spring 51 acts between the cross pin50 and the lower most third flange 43 and is a yieldable means urgingthe lock bar 48 up wardly through the first and second flanges 41 and42.

The flexible drive member or chain 26 is constructed like an ordinarybicycle chain with alternate pairs of widely spaced and more closelyspaced links 52 and 53, respectively. Each of these links has a narrowedwaist 54 between enlarged ends 55 at which the rollers 56 are pivotallyengaged with these enlarged ends 55. A vertical wall 58 is provided onthe load carriage 30 between the first and second flanges 41 and 42 andthis vertical wall is provided with an undulating surface 59 having acrest 60. The lock bar 48 in its upwardly urged position is parallel tothis vertical wall 58 and is spaced from the crest 60 by a transversehorizontal dimension greater than the transverse dimension of thenarrowed waist 54 of the links yet less than the transverse dimensionacross the enlarged ends 55 of such links. Accordingly when the lock bar48 is urged upwardly by the spring 51 into the position shown in FIGS.2, 3 and 4, the engaging means 35 establishes that the chain 26 iseffectively locked to the load carriage 30.v

A latch wall 62 depends from the base 36. This latch wall is verticaland parallel to the lock bar 48. A latch notch 63 is formed in the lowersurface of this latch wall 62 and cam walls 64 and 65 are provided oneither side of the notch 63. The cross pin 50 may engage the cam walls64 or 65 and ultimately the latch notch 63 whenever the lock bar 48 ispulled downwardly and rotated. When this cross pin 50 does latchinglyengage the latch notch 63, then the upper end of this lock bar 48 isdisposed below the level of the upper surface of the second flange 42,and thus the load carriage 30 is completely disengaged from the chain26. Accordingly a person may easily grasp the handle 49, pull downwardlyon the lock bar 48 and rotate the handle approximately 150 or 180 tohave the cross pin 50 engage this latch notch 63. At this time the loadcarriage is then disengaged from the chain and accordingly the door 12is disengaged from the garage door operator which is the motor 16 andspeed-reducing drive train 17. This is useful on those rare occasionswhen the electrical power fails and it is necessary to disengage thedrive mechanism 11 so that the door 12 may be manually opened or closed.It will be noted that in such condition the load carriage 30 is stilllongitudinally slidably guided by the frame extension 19 so that theupper end of the door arm 31 does not swing uncontrollably as the garagedoor is opened thus eliminating the possibility that this door maydamage the automobile or injure someone in the garage. In many prior artdevices some pivot connection such as the pivot connection 32 has to bedisengaged in order to disconnect the drive mechanism 11 from the door12. Not only was this dangerous but this was often very difficult to dowhen the garage door was closed because the load carriage 30 usuallyassumes a position directly above the garage door 12 so that a toggleaction is provided effectively locking the door closed when the garagedoor operator 16-17 is deenergized. In this toggle locking position ofthe door 12, there is considerable shearing stress placed on the pivotconnection 32 and thus even though the nut is removed from the bolt ofthis pivot connection, it is often very difficult to remove this boltfrom the fork 40 and door arm 31. This is another advantage of thepresent invention because the lock bar 48 may be easily retracted fromits engaged position toward its disengaged position.

Also, it will be noted that the lock bar 48 engages the closely spacedlinks 53 andv engages between the widely spaced links 52, as shown inFIGS. 2 and 3. Alternatively the lock bar 48 may engage the widelyspaced links 52 and engage between the closely spaced links 53. This maybe accomplished by moving the chain along to the next set of links. inany event the lock bar 48 engages the links at the narrowed waists 54.

This engagement with the chain is an engagement with a flexible drivemember and one advantage is that this flexible drive member may be madeas an endless chain so that installation problems are simplified and theinstaller does not need to connect the ends of the chain to a doorcarriage nor to some adjustment device such as a turnbuckle. [n thepresent case the idler roller 25 may be made adjustable by being on aslide block adjustably moved by a screw so as to take up for wear whichwould cause slack in the two runs 27 and 28 of the chain 26.

The engaging means 35 provides a selectable engagement or disengagementbetween the chain 26 and the load carriage 30. In this preferredembodiment the engaging means is mounted on the load carriage. The chain26 is an elongated member which has varying transverse dimensionsincluding the narrowed waists 54 and the enlarged ends 55. The lock bar48 by engaging the links of the chain permits transmission of forcelengthwise of the chain to the load carriage 30, yet the lock bar 48 maybe easily withdrawn from engagement with the chain by movement of thelock bar in a direction transverse to the lengthwise dimension of thechain. It will be noted by observing FIG. 2 that the lock bar 48 movesbetween engaged and disengaged positions by movement substantiallyparallel to the rollers or pivots 56 of the chain 26. By theabove-described construction it will be noted that the lock bar 48 mayselectively engage the chain at any desired position along the length ofthis chain. The latch notch 63 engaging the cross pin 50 is a latchmeans or detent means which selectively will hold the lock bar 48 in adisengaged condition.

The present disclosure includes that contained in the appended claims,as well as that of the foregoing description. Although this inventionhas been described in its preferred form with a certain degree ofparticularity, it is understood that the present disclosure of thepreferred form has been made only by wayof example and that numerouschanges in the details of the circuit and the combination andarrangement of circuit elements may be resorted to without departingfrom the spirit and scope of the invention as hereinafter claimed.

What is claimed is:

l. A drive mechanism for a load comprising, in combination, a frame,

a motor on said frame,

a speed-reducing drive train on said frame and having an input from saidmotor,

a flexible drive member drivingly connected to said rotatable output,

a load carriage,

means for longitudinally guiding movements of said carriage generallyparallel to a portion of said flexible drive member,

means for attaching said load carriage to a load to be moved,

a chain having links included in said flexible drive member,

narrowed waists between enlarged ends on said chain links,

and engaging means selectively engaging and disengaging said loadcarriage and said chain at a narrowed waist to transmit force lengthwiseof said chain to said carriage by abutment of an enlarged end of a linkwith said engaging means.

2. A drive mechanism as set forth in claim 1, wherein said chain haspivots between links, and said engaging means moves substantiallyparallel to said pivots between engaged and disengaged conditions.

3. A drive mechanism for a load comprising, in combination, a frame,

a motor on said frame,

a speed-reducing drive train on said frame and having an input from saidmotor,

a rotatable output on said drive train,

a flexible drive member drivingly connected to said rotatable output,

a load carriage,

means for longitudinally guiding movements of said carriage generallyparallel to a portion of said flexible drive member,

means for attaching said load carriage to a load to be moved,

a chain having links included in said flexible drive member,

engaging means selectively engaging and disengaging said load carriageand said chain,

said chain engaging means including three vertically spaced horizontalflanges on said carriage,

vertically aligned apertures in said flanges,

a vertical lock bar slidable and rotatable in said vertically alignedapertures,

and a handle on the lower end of said lock bar to move said lock bar insaid apertures to a disengaged condition relative to said chain.

4. A drive mechanism as set forth in claim 3, including a cross pin insaid lock bar disposed below said second flange,

and a compression spring encircling said lock bar and disposed betweensaid third flange and said cross pin to urge said lock bar upwardly.

5. A drive mechanism as set forth in claim 4, including said first andsecond flanges lying above and below one run of said chain,

a vertical wall between said first and second flanges,

an undulating surface with a crest on said vertical wall to lie closelyadjacent the links of said chain,

said chain links having narrowed waists between enlarged ends,

and said lock bar when disposed in the apertures in said first andsecond flanges defining relative to the crest of said undulating surfacea transverse horizontal dimension greater than the transverse dimensionof the narrowed waist of the links of the chain and less than thedimension across the enlarged ends of the links of said chain.

6. A drive mechanism as set forth in claim 4, including a latch wallspaced between said second and third flanges,

a notch in said latch wall adapted to be engaged by said cross pin uponsaid lock bar being moved longitudinally to stress said compressionspring and move said lock bar to a disengaged position relative to saidchain and then said lock bar being rotated.

7. A drive mechanism as set forth in claim 6, including a cam wall oneach side of said notch and cooperable with said cross pin.

8. A load carriage for use with a drive mechanism having a chain withlinks driving a load relative to a frame,

said chain links having narrowed waists between enlarged ends,

said load carriage comprising, in combination,

means guiding movement of said load carriage on the frame generallyparallel to a portion of the chain,

means for attaching said load carriage to a load to be moved, andengaging means selectively engaging and disengaging said load carriageand the chain at a narrowed waist to transmit force lengthwise of thechain to said carriage by 5 abutment of an enlarged end of a link withsaid engaging means. 9. A load carriage for use with a drive mechanismhaving a chain with links driving a load relative to a frame,

said load carriage comprising, in combination,

10 means guiding movement of said load carriage on the frame generallyparallel to a portion of the chain, means for attaching said loadcarriage to a load to be moved, engaging means selectively engaging anddisengaging said load carriage and the chain,

the chain-engaging means including three vertically spaced horizontalflanges on said carriage, vertically aligned apertures in said flanges,a vertical lock bar slidable and rotatable in said vertically aligned aertures,

and a hand e on the lower end of said lock bar to move said lock bar insaid apertures to a disengaged condition relative to the chain.

10. A drive mechanism as set forth in claim 9, including a cross pin insaid lock bar disposed below said second flange,

and a compression spring encircling said lock bar and disposed betweensaid third flange and said cross pin to urge said lock bar upwardly.

11. A drive mechanism as set forth in claim 10, including said first andsecond flanges lying above and below one run of the chain,

a vertical wall between said first and second flanges,

an undulating surface with a crest on said vertical wall to lie closelyadjacent the links of the chain,

the chain links having narrowed waists between enlarged ends,

said lock bars when disposed in the apertures in said first and secondflanges defining relative to the crest of said undulating surface atransverse horizontal dimension greater than the transverse dimension ofthe narrowed waist of the links of the chain and less than the dimensionacross the enlarged ends of the links of the chain.

12. A drive mechanism as set forth in claim 10, including a latch wallspaced between said second and third flanges,

a notch in said latch wall adapted to be engaged by said cross pin uponsaid lock bar being moved longitudinally to stress said compressionspring and move said lock bar to a disengaged position relative to thechain and then said lock bar being rotated.

13. A drive mechanism as set forth in claim 12, including a cam wall oneach side of said notch and cooperable with said cross pin.

1. A drive mechanism for a load comprising, in combination, a frame, a motor on said frame, a speed-reducing drive train on said frame and having an input from said motor, a flexible drive member drivingly connected to said rotatable output, a load carriage, means for longitudinally guiding movements of said carriage generally parallel to a portion of said flexible drive member, means for attaching said load carriage to a load to be moved, a chain having links included in said flexible drive member, narrowed waists between enlarged ends on said chain links, and engaging means selectively engaging and disengaging said load carriage and said chain at a narrowed waist to transmit force lengthwise of said chain to said carriage by abutment of an enlarged end of a link with said engaging means.
 2. A drive mechanism as set forth in claim 1, wherein said chain has pivots between links, and said engaging means moves substantially parallel to said pivots between engaged and disengaged conditions.
 3. A drive mechanism for a load comprising, in combination, a frame, a motor on said frame, a speed-reducing drive train on said frame and having an input from said motor, a rotatable output on said drive train, a flexible drive member drivingly connected to said rotatable output, a load carriage, means for longitudinally guiding movements of said carriage generally parallel to a portion of said flexible drive member, means for attaching said load carriage to a load to be moved, a chain having links included in said flexible drive member, engaging means selectively engaging and disengaging said load carriage and said chain, said chain engaging means including three vertically spaced horizontal flanges on said carriage, vertically aligned apertures in said flanges, a vertical lock bar slidable and rotatable in said vertically aligned apertures, and a handle on the lower end of said lock bar to move said lock bar in said apertures to a disengaged condition relative to said chain.
 4. A drive mechanism as set forth in claim 3, including a cross pin in said lock bar disposed below said second flange, and a compression spring encircling said lock bar and disposed between said third flange and said cross pin to urge said lock bar upwardly.
 5. A drive mechanism as set forth in claim 4, including said first and second flanges lying above and below one run of said chain, a vertical wall between said first and second flanges, an undulating surface with a crest on said vertical wall to lie closely adjacent the links of said chain, said chain links having narrowed waists between enlarged ends, and said lock bar when disposed in the apertures in said first and second flanges defining relative to the crest of said undulating surface a transverse horizontal dimension greater than the transverse dimension of the narrowed waist of the links of the chain and less than the dimension across the enlarged ends of the links of said chain.
 6. A drive mechanism as set forth in claim 4, including a latch wall spaced between said second and third flanges, a notch in said latch wall adapted to be engaged by said cross pin upon said lock bar being moved longitudinally to stress said compression spring and move said lock bar to a disengaged position relative to said chain and then said lock bar being rotated.
 7. A drive mechanism as set forth in claim 6, including a cam wall on each side of said notch and cooperable with said cross pin.
 8. A load carriage for use with a drive mechanism having a chain with links driving a load relative to a frame, said chain links having narrowed waists between enlarged ends, said load cArriage comprising, in combination, means guiding movement of said load carriage on the frame generally parallel to a portion of the chain, means for attaching said load carriage to a load to be moved, and engaging means selectively engaging and disengaging said load carriage and the chain at a narrowed waist to transmit force lengthwise of the chain to said carriage by abutment of an enlarged end of a link with said engaging means.
 9. A load carriage for use with a drive mechanism having a chain with links driving a load relative to a frame, said load carriage comprising, in combination, means guiding movement of said load carriage on the frame generally parallel to a portion of the chain, means for attaching said load carriage to a load to be moved, engaging means selectively engaging and disengaging said load carriage and the chain, the chain-engaging means including three vertically spaced horizontal flanges on said carriage, vertically aligned apertures in said flanges, a vertical lock bar slidable and rotatable in said vertically aligned apertures, and a handle on the lower end of said lock bar to move said lock bar in said apertures to a disengaged condition relative to the chain.
 10. A drive mechanism as set forth in claim 9, including a cross pin in said lock bar disposed below said second flange, and a compression spring encircling said lock bar and disposed between said third flange and said cross pin to urge said lock bar upwardly.
 11. A drive mechanism as set forth in claim 10, including said first and second flanges lying above and below one run of the chain, a vertical wall between said first and second flanges, an undulating surface with a crest on said vertical wall to lie closely adjacent the links of the chain, the chain links having narrowed waists between enlarged ends, said lock bars when disposed in the apertures in said first and second flanges defining relative to the crest of said undulating surface a transverse horizontal dimension greater than the transverse dimension of the narrowed waist of the links of the chain and less than the dimension across the enlarged ends of the links of the chain.
 12. A drive mechanism as set forth in claim 10, including a latch wall spaced between said second and third flanges, a notch in said latch wall adapted to be engaged by said cross pin upon said lock bar being moved longitudinally to stress said compression spring and move said lock bar to a disengaged position relative to the chain and then said lock bar being rotated.
 13. A drive mechanism as set forth in claim 12, including a cam wall on each side of said notch and cooperable with said cross pin. 